San Juan had often been a connecting point for us when travelling to the Caribbean. There are numerous flights to San Juan out of the NY area which makes it very convenient to route through. Our most recent trip; San Juan was our final stop.
The airport itself is nice but the airport staff; gate agents in particular need to brush up on their people skills.
Getting out of the San Juan airport was a breeze, then again it was almost midnight so maybe that's not representative of the normal. If you are traveling from the US, you do not need a passport to enter Puerto Rico since it's a US territory nor do you go through customs. On the way home you have to pass your bags through a check by the USDA before you check in with your airline, both hand luggage and checked luggage. Give yourself at least 2 hours, the lines at United were very slow and the lines through security were very slow and there were lots of people who obviously thought you could get to the airport with much less time than that as they were letting them all cut in line so they didn't miss their planes.
I flew with American Airlines from JFK to San Juan. I paid $237 including taxes, it would be $5 cheaper if I bought them online but it didn't seem to work out so I had to call the office instead. On my way from JFK to SJU, the plane was delayed for about 30 minutes but it was like 3 hours for SJU to JFK. The flight took about 3 hours and 50 minutes. I would suggest trying to fly to San Juan or leave during the day time once to be able to see Puerto Rico from a bird's eyes view. It's really cool.
I would say AA is definitely one of the cheapest airlines to fly to San Juan. You can also try www.jetblue.com but you need to book way in advance to get $79 for each way but adding $19.60 for taxes, it doesn't really make any difference from AA anyway.
This must be the most confusing airport I have ever seen. You exit into the check-in area, then you have to exit and get down to ground level to catch a taxi. There is a booth with a couple of girls; you tell them where you go, and they give you a ticket.
Luis Marin Airport (SJU) is the main airport serving Puerto Rico. It is located in the eastern part of the city.